This paper describes a disturbance acceleration adaptive estimate and correction approach for an attitude reference system (ARS) so as to improve the attitude estimate precision under vehicle movement conditions. The proposed approach depends on a Kalman filter, where the attitude error, the gyroscope zero offset error and the disturbance acceleration error are estimated. By switching the filter decay coefficient of the disturbance acceleration model in different acceleration modes, the disturbance acceleration is adaptively estimated and corrected, and then the attitude estimate precision is improved. The filter was tested in three different disturbance acceleration modes (non-acceleration, vibration-acceleration and sustained-acceleration mode, respectively) by digital simulation. Moreover, the proposed approach was tested in a kinematic vehicle experiment as well. Using the designed simulations and kinematic vehicle experiments, it has been shown that the disturbance acceleration of each mode can be accurately estimated and corrected. Moreover, compared with the complementary filter, the experimental results have explicitly demonstrated the proposed approach further improves the attitude estimate precision under vehicle movement conditions.

Landslides caused by earthquakes and other natural disasters may cause serious economic and personal losses. Slope protections are usually applied in engineering practice to prevent significant slope slides and damages. Based on the mechanical and ecological requirements on slope protections, this paper put forward a new type of anchor + hinged block ecological slope and carried out shaking table tests on it and other three traditional slope protections for comparing. By shaking table tests, the acceleration amplification factors and Fourier amplitude spectrums of four different slope types are analyzed and compared to verify the suitability of this new slope protection under earthquakes. The results indicated that the natural frequency and the acceleration Fourier amplitude spectrum of the four tested slope protections change according to internal materials. The anchor + hinged block ecological slope has higher natural frequency comparing to traditional slopes, so the resonance cycle from earthquake excitation can effectively be avoided and as a result the anchor + hinged block ecological slope can achieve better seismic performance.

In acceleration and vibration environment, to weaken frequency instability influence of the crystal oscillator on GPS carrier loop and rectify frequency compensation, researchers usually adopt the solution of crystal oscillator frequency acceleration compensation. The vital basis of compensating frequency errors is how to obtain accurately corresponding sensitive parameters of crystal oscillator. In the traditional calibration approach of acceleration sensitivity coefficient, indispensably using precise frequency reference and measurement equipment makes the calibration process expensive and complex, that fails to be widely applied in GPS navigation system. Combined a precise frequency reference of GPS satellites with the carrier tracking loop principle, the paper analyzes the acceleration frequency errors transmission mechanism of crystal oscillator in the carrier tracking loop, and designs an adaptive weighted EKF to handle frequency bias observed values synchronously in multiple tracking loops, which reduces frequency bias estimating noise and separates frequency offset and frequency drift rate, from the receiver's frequency bias observation in the crystal oscillator. And on this basis, acceleration sensitivity coefficients of crystal oscillator calibrate on the super tight combination navigation board by 2g flipping calibration method. The experiments show that the method is able to effectively calibrate acceleration sensitivity coefficients of crystal oscillator, which is the solution base of compensating crystal oscillator acceleration frequency errors on related GPS technology research.

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